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- 1. Lake Habitat Survey (LHS) provides a standard method for characterizing the physical habitat of lakes and reservoirs, but has not been tested for its relevance to the composition and abundance of macroinvertebrates. This study investigated the relationship between the metrics used in LHS and components of macroinvertebrate communities found in the littoral zone of a shallow calcareous lake in the west of Ireland.
- 2. A scoring system, the Habitat Quality Assessment (HabQA), developed from the Lake Habitat Quality Assessment (LHQA) of the LHS, was used to assess the relationship between habitat quality based on physical structure within 10 LHS ‘habplots’ and metrics of the macroinvertebrate community.
- 3. Macroinvertebrate taxon richness, both of adults found in the riparian zone and larvae found in the littoral zone, correlated positively with the HabQA score. Macrophytes within the littoral zone, and complexity of riparian vegetation within the riparian zone, were particularly important in driving the HabQA score. While overall abundance of macroinvertebrates did not vary with HabQA score, that of particular genera did.
- 4. The HabQA score was a useful surrogate of taxon richness for adult and larval aquatic macroinvertebrates, suggesting that, in general, LHS provides a useful conservation assessment tool relevant for macroinvertebrates. However, in some circumstances, such as wave‐washed stony substrates devoid of macrophytes, the HabQA score may not capture the quality of a site for macroinvertebrates, and the importance of natural but low diversity sites should not be neglected in conservation assessment of lakes. Similarly, while the LHS method notes the presence of alien species, further work on how these could be incorporated into the method would be useful.
- 5. Reliance on a single, or overall combined, metric score across quality elements, whether based on biotic or structural assessment, has some potential limitations. It is clear that for conservation management a holistic assessment of naturalness, representativeness and species rarity needs to be made in conjunction with scoring systems.
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Francisco García‐Criado Eloy Bcares Camino Fernndez‐Alez Margarita Fernndez‐Alez 《水产资源保护:海洋与淡水生态系统》2005,15(1):31-50
- 1. The EC Water Framework Directive requires that Member States assess the ecological quality of their water bodies on the basis of a wide set of variables, including benthic invertebrates.
- 2. The aim of the study was to find one or more faunistic indices that could be related to ecological status of shallow lakes, independent of different macrophyte types.
- 3. Six invertebrate indices were calculated from abundance and biomass data in 10 Spanish shallow lakes: total abundance and biomass, Shannon's index, percentage of predators, percentage of Ephemeroptera, Plecoptera and Trichoptera, Orthocladiinae as a percentage of the total Chironomidae, and Chironominae as a percentage of the whole macroinvertebrate community. Taxon richness was also calculated.
- 4. Differences in the values of indices across different macrophyte types were explored by means of a one‐way analysis of variance. Significant differences were occasionally found when indices were calculated from biomass data. Total abundance was also significantly different across some architecture types.
- 5. No significant correlations were found between the overall values of the indices for each lake and the environmental variables measured (ecological status, total nitrogen, total phosphorus, chlorophyll a concentrations, dynamics of the water flow, and naturalness of the shore), except in the case of total biomass.
- 6. Values of indices were plotted (box plots) to detect potential differences between lakes of different ecological status. None of the index values was clearly related to ecological status. Thus, the approach used here, requiring relatively little sampling effort and taxonomic expertise, was of little use as a quality indicator for shallow lakes. The implementation of the Directive will therefore require different approaches to be developed and tested.
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《水产资源保护:海洋与淡水生态系统》2003,13(6):507-549
- 1. The European Water Framework Directive requires the determination of ecological status in European fresh and saline waters. This is to be through the establishment of a typology of surface water bodies, the determination of reference (high status) conditions in each element (ecotype) of the typology and of lower grades of status (good, moderate, poor and bad) for each ecotype. It then requires classification of the status of the water bodies and their restoration to at least ‘good status’ in a specified period.
- 2. Though there are many methods for assessing water quality, none has the scope of that defined in the Directive. The provisions of the Directive require a wide range of variables to be measured and give only general guidance as to how systems of classification should be established. This raises issues of comparability across States and of the costs of making the determinations.
- 3. Using expert workshops and subsequent field testing, a practicable pan‐European typology and classification system has been developed for shallow lakes, which can easily be extended to all lakes. It is parsimonious in its choice of determinands, but based on current limnological understanding and therefore as cost‐effective as possible.
- 4. A core typology is described, which can be expanded easily in particular States to meet local conditions. The core includes 48 ecotypes across the entire European climate gradient and incorporates climate, lake area, geology of the catchment and conductivity.
- 5. The classification system is founded on a liberal interpretation of Annexes in the Directive and uses variables that are inexpensive to measure and ecologically relevant. The need for taxonomic expertise is minimized.
- 6. The scheme has been through eight iterations, two of which were tested in the field on tranches of 66 lakes. The final version, Version 8, is offered for operational testing and further refinement by statutory authorities.
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Cristina Trigal‐Domínguez Camino Fernández‐Aláez Francisco García‐Criado 《水产资源保护:海洋与淡水生态系统》2009,19(7):786-796
- 1. Habitat heterogeneity has many implications in ecological assessment studies. On one hand it provides varying niches for organisms, increasing diversity. On the other hand, the inherent spatial variability of structurally complex systems may overlap with ecological condition making it difficult to disentangle the effects of perturbation. This study investigated the combined and single effects of habitat and pond condition on the macroinvertebrate assemblages of 35 ponds located in north‐west Spain and spanning a range of water quality and habitat characteristics.
- 2. Macroinvertebrate communities and several environmental variables were sampled in the summer of 2004 or 2003. Samples were collected from four dominant habitats (vegetated shores, shores without vegetation, submerged vegetation, bare sediments) following a time‐limited sampling. Non‐metric multidimensional scaling and two‐way crossed ANOSIM were used to investigate the taxonomic and functional differences in macroinvertebrate assemblage structure among habitats (four types) and pond conditions (optimal, good, moderate, poor, very poor). To investigate the individual and combined effects of pond condition and habitat on several diversity measures GLM models were used. In addition, the accuracy of two sampling designs — stratified and multihabitat — was compared using the CVs of seven macroinvertebrate attributes.
- 3. Results showed that macroinvertebrate communities differed significantly, albeit weakly, among habitat types and pond condition categories. In particular, the abundance of several Chironomidae genera, rarefied richness and Shannon index decreased both in perturbed systems and bare sediments, whereas no marked differences occurred between shores and submerged vegetation.
- 4. We suggest that a multihabitat approach together with the use of community attributes not (or slightly) affected by habitat type will provide more comparable results across ponds than a stratified approach or observation of the whole community, especially in ponds where degradation leads to habitat loss.Copyright © 2009 John Wiley & Sons, Ltd.
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- 1. The Water Framework Directive (WFD) requires member states to establish ‘type‐specific biological reference conditions’ for the assessment of surface waters and describes a method for establishing such biological targets. The methodology described in the Directive is based on geographic and physical characteristics and similar to the ‘multimetric’ approach used widely in North America, but contrasts with the biological classification of the ‘multivariate’ approach which is commonly used in Europe.
- 2. An investigation was made of the relative efficiency of the multimetric and multivariate classification approaches in partitioning the observed biological variation of the macroinvertebrate communities of 22 minimally disturbed lakes in Northern Ireland. Furthermore, the accuracy of predictive models based on the two approaches was compared.
- 3. The WFD environmental typologies partitioned the observed biological variation poorly with a maximum ANOSIM R‐value of 0.216 compared with 0.609 for a multivariate biological site classification. The WFD System B approach partitioned more variation than the System A approach.
- 4. The use of a predictive model, based on any of the site classification approaches, resulted in more accurate faunal predictions than a null model. However, the biological model produced the most accurate predictions.
- 5. Canonical correspondence analysis showed that the environmental variables used in the biological classification model explained more variation (28%) than the best‐performing environmental classification model (24%). The most important variable was pH, followed by surface area and altitude. The variables used in all approaches explained more variation when used as continuous rather than categorized parameters.
- 6. The results of this work, the first such comparative study of predictive models in lakes, concur with similar studies in streams. It may be concluded that large‐scale environmental classifications are unreliable as a method for setting type‐specific reference targets for the ecological assessment of fresh waters.
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Kieran A. Monaghan Ana L. Machado Frederick J. Wrona Amadeu M.V.M. Soares 《水产资源保护:海洋与淡水生态系统》2020,30(4):662-674
- The increasing risk of wildfire has focused attention on the timescale of the impact and recovery of river ecosystems and methods for their bioassessment.
- An 18‐year pseudo time‐series was exploited to document patterns in benthic macroinvertebrate impact and recovery and evaluate the efficacy of alternative metrics to assess fire damage. Macroinvertebrates were surveyed by kick‐sampling and data were collected on river habitats. Details of river catchments and wildfire were collated as a GIS database.
- Macroinvertebrate richness and abundance recovered rapidly, marked by a phase of dynamic increase, followed by relative stability (0–2 years and 3–18 years, respectively). Across sites, richness and abundance were best explained by time since fire.
- A biotic index of general river quality was ineffective as an indicator of fire damage. While a metric of K‐selected taxa (Odonata richness) was generally indicative of fire‐affected assemblages, a contrasting metric of r‐selected taxa (percentage of chironomids, baetids, and simuliids) was not.
- Ordination analysis revealed time as a significant determinant of community structure across sites; however, its overall statistical importance was eclipsed by habitat characteristics (water quality, shade, altitude, and latitude) that were associated with ecological variation across both recently affected sites and the putatively recovered communities.
- These results highlight the stochastic processes – environmental and ecological – that frame the macroinvertebrate response to wildfire. This probabilistic context emphasizes the difficulties of developing indicator taxa for wildfire bioassessment and reinforces the importance of standardized survey protocols and the use of contrasting metrics in the assessment of wildfire impact on the ecological quality of rivers.
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- 1. Classification is a useful tool for researchers and managers wishing to group functionally similar sites or to identify unique or threatened habitats. A process‐based river classification scheme that successfully integrates physical and biological aspects of lotic form and function would enhance conservation and restoration efforts by allowing more meaningful comparisons among sites, and improving functional understanding of lotic ecosystems.
- 2. The River Styles framework provides a geomorphological river characterization scheme in which assemblages of geomorphic units vary for differing River Styles, presenting differing arrays of aquatic habitat diversity for each style.
- 3. The ecological significance of the River Styles framework is tested by comparing the macroinvertebrate assemblages and habitat characteristics of pool and run geomorphic units for three different River Styles on the north coast of New South Wales, Australia.
- 4. Multivariate ordinations and analysis of similarity (ANOSIM) revealed that macroinvertebrate community structure differed between Bedrock‐Controlled Discontinuous Floodplain rivers and Gorge rivers, and between Bedrock‐Controlled Discontinuous Floodplain and Meandering Gravel Bed rivers, especially in pools. Differences between Gorge and Meandering Gravel Bed rivers were less apparent, largely due to variations within the Meandering Gravel Bed rivers group.
- 5. The variability in macroinvertebrate assemblage structure among geomorphic units was most strongly related to variability in substrate and hydraulic variables. Substrate composition differed significantly among all River Styles and geomorphic units, but other habitat variables showed few consistent differences among River Style groups.
- 6. These results suggest that the ecological similarity of macroinvertebrate communities within River Styles may presently be limited because some important large‐scale drivers of local habitat conditions are not included in River Styles designations. Integrating River Styles classification with other large‐scale variables reflecting stream size, temperature and hydrological regime may produce a process‐based physical classification capable of identifying river reaches with similar ecological structure and function.
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J.S. Rowan J. Carwardine R.W. Duck O.M. Bragg A.R. Black M.E.J. Cutler I. Soutar P.J. Boon 《水产资源保护:海洋与淡水生态系统》2006,16(6):637-657
- 1. In the absence of a standard procedure for characterizing the physical habitat of lakes in Europe, this paper describes the development of a multi‐purpose Lake Habitat Survey (LHS). The technique has been designed to meet the hydromorphological assessment needs of the Water Framework Directive (WFD), as well as to assist in monitoring the condition of designated sites in the UK and for wider application in environmental impact assessments and restoration programmes.
- 2. LHS involves detailed recording of shoreline features at a number of plots (Hab‐Plots), complemented by a meso‐scale survey of the entire lake, including shoreline characteristics and pressures, and modifications to the hydrological regime. A temperature and dissolved oxygen profile is also compiled at the deepest point of the lake (Index Site). Existing databases are exploited where possible, and remote sensing data (e.g. aerial photographs) are used to assist field‐based observations.
- 3. Initial field trials demonstrated that the consistency of the method, whether conducted by boat or on foot, was high. More than 250 surveys were carried out across the UK in 2004 through collaboration with the statutory environment and conservation agencies.
- 4. Two levels of complexity were tested — a full version requiring 10 Hab‐Plots and an abridged version, LHScore, involving four plots and omitting the Index Site. While 8–10 plots were required to capture the full diversity of features at complex sites, LHScore data were sufficient to generate metrics for classification purposes.
- 5. A Lake Habitat Modification Score (LHMS) may be calculated from LHS data. This synthesizes a wide array of hydromorphological and human pressures and has direct applications for assessment of ecological status under the WFD. Preliminary analysis illustrates a spectrum of hydromorphological alteration of 82 lakes in the UK.
- 6. Further considerations are discussed, including the prospect that the LHS protocol might form the basis of a European standard developed through CEN (Comité Européen de Normalisation).